The purpose of this study was to observe corrosion characteristics of six dental amalgams and was to analyse corrosion products electrochemically. After each amalgam alloy and Hg was triturated as the direction of the manufacturer by using
mechanical
amalgamator, the triturated mass was inserted into the cylinderical metal mold(12×10mm) and was condensed with 160kg/cm* by using the hydrolic press. The specimen was removed from the mold and was stored at room temperature for 1 week, and was
polished
with amalgam polishing kit. The anodic and cathodic polarization curve was obtained by using cyclic voltammetric method with 3-electrode potentiostat in saline for each amalgam and Ag, Sn, Cu plate specimen at 37 * 0.5℃. The potential sweep
range
was
-1.7V∼0.4V(vs SCE) in working electrode and scan rate was 50mV/s and the exposed surface area of each specimen to the electrolytic solution was 0.79cm2.
The results were as follows
1. In anodic-cathodic polarization curve of amalgam specimens, tow anodic current rising areas and two cathodic current peaks were obtained at thelow Cu amalgam (CF, CS) specimen and three anodic current rising areas and three cathodic current
peaks
were obtained at the high Cu amalgam (TY, DS, HV) specimen.
2. As this compared with the anodic and cathodic current peak potentials of Sn, Cu and Ag specimen, the first cathodic current peak I c was caused by the reduction of divalent tin salt, second cathodic current peak II c results from the
reduction
of
quadravalent tin aslt, and third cathodic current peak III c results from the reduction of copper salt.
3. As reversed potential sweeping was done repeatedly, anodic current was decreased slightly in all amalgam specimens.
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